The neuroplasticity bait-and-switch


As long as we’re talking about brains this morning, here’s another topic that irritates me: the abuse of the term neuroplasticity.

devneuro

Way, way back in the late 1970s, my first textbook in neuroscience was this one: Marcus Jacobson’s Developmental Neurobiology. (That link is to a more recent edition; the picture is of the blue-and-black cover I remember very well, having read the whole thing). I came into the field by way of developmental biology, and that means we focused on all the changes that go on in the brain: everything from early tissue formation to senescence, with discussions of synaptogenesis, remodeling, metabolism, transport, and functional responses to activity or inactivity. This is all under the broad umbrella of neuroplasticity, a term that’s at least a century old, and that is well-established as both a phenomenon and a science. That the brain modifies itself in response to experience is so thoroughly taken for granted that you can basically define neuroscience as the study of the responsiveness of neural tissue.

So I’m reading this interview with Norman Doidge, huckster of neuroplasticity, and I could not control my eyebrows, which started climbing up my forehead and felt like they were ascending the crown and considering a descent down to my neck. It’s not just that Doidge is so full of shit that it’s dribbling out his ears, it was the shamefully ignorant questions of the interviewer, Tim Adams. Look at this question:

One of the things that struck me, reading your books, is how entrenched our ideas of the brain’s essential fixed and unregenerative nature are. Why are those ideas so powerful?

Whoa right there. How could anyone have the idea that neuroscientists think the brain is essentially fixed and unregenerative? That’s painfully counterfactual, the precise opposite of the actual position of the field of neurobiology. Conveniently, Adams has already answered how he came by such a bogus idea: by reading Doidge’s books. That should tell you something about the worth of Doidge’s stories.

Doidge’s first book, published seven years ago, described how the principle of such healing – of the plastic brain – was becoming established fact in the laboratory through a greater understanding of ways in which circuits of neurons functioned and were created by thought. “Equipped,” Doidge wrote, “for the first time, with the tools to observe the living brain’s microscopic activities, neuroplasticians showed that the brain changes as it works. In 2000, the Nobel prize for medicine was awarded for demonstrating that, as learning occurs, the connections among nerve cells increase. The scientist behind that discovery, Eric Kandel, also showed that learning can ‘switch on’ genes that change neural structure. Hundreds of studies went on to demonstrate that mental activity is not only the product of the brain but the shaper of it.”

Christ. Wrong.

I got my Ph.D. in 1985 for studies on changing spinal circuitry in the zebrafish spinal cord. I didn’t get the Nobel for it because the idea that synapses form and change gradually and integrate new elements of the circuit was not new or revolutionary; I was filling in details on a specific organism, working within a model of neural function that basically everyone accepts. Kandel (and Carlsson and Greengard) won the Nobel prize for a large body of work on signal transduction in the nervous system. That the brain changes as it works isn’t novel; working out the details, the specific molecules and pathways involved, was, especially since they had the potential to help address human disease. Doidge’s “think yourself better” approach doesn’t.

Here comes the bait-and-switch:

You suggest often that neuroplasticity is settled fact. That doesn’t seem to me to be the case in the medical profession and certainly not beyond it…

Within the lab, within science, within neurophysiology, neuroplasticity is established fact – nobody is challenging it.

So on the one hand, Doidge is claiming that the idea of the brain being this fixed and inflexible organ is entrenched; on the other, that neuroplasticity is an unchallenged fact. Which is it?

That the brain is capable of structural, molecular, chemical, and electrical changes in response to the environment is absolutely a fact, accepted without question by the field as a whole. That isn’t a lump of phlegm in your cranium.

But what Doidge does is conflate the scientific understanding of neuroplasticity with his brand of quackery and hype. Doidge claims much more, using poorly sourced anecdotes of people curing themselves of Parkinson’s or restoring their sight by thinking and carrying out various exercises.

The medical establishment has been well aware of the capacity of the brain to repair itself for years: you do know that there are all kinds of established therapies for stroke patients, right? There is no denial of the regenerative capacity of the brain, or that it rewires itself to meet circumstances. Quacks like Doidge rely on misrepresenting the known science to make standard treatments look like a miraculous consequence of his innovative and revolutionary thinking (they aren’t), and to exaggerate the effects of his claims.

You cannot cure Parkinson’s by concentrating really hard while walking. You can learn to compensate for some of the effects of the disease. Eye exercises will not cure degenerative retinopathies. Let’s not sell false hope.

And this just infuriates me:

Yes, well I didn’t set out to do that. When I finished my first book I had come to the conclusion that many of the claims that eastern medicine was making, which led to a lot of eye-rolling among western doctors, had at least to be re-examined in the light of neuroplasticity. By the time I had finished The Brain That Changes Itself, there were significant studies, which no one disputes, which show major changes in the structure of the brain of Tibetan monks, for example, brought about through the practice of meditation. I suppose it is not really a hard sell once you have grasped that the brain is plastic, that someone who has spent 30,000 hours meditating might actually have changed the structure of their brain. I mean, a London taxi driver can change his brain by studying routes through the city for a year or two.

Aaaaargh. That’s right. No one disputes the idea that spending years doing something changes the brain. Tibetan monks get better at meditating, whatever that means; taxi drivers get familiar with travel routes; video game players get better at their games; surgeons get better at surgery with practice. It’s kind of the whole sine qua non of learning.

Doidge didn’t discover it, and it does have limitations. Don’t fall for the neuroplasticity hype — it’s promoted by charlatans who inflate its significance far beyond the fundamental utility of the concept into vast magical realms of nonsense that verge on the Secret, the ‘Law’ of Attraction, and the Power of Positive Thinking. All bunk.

Comments

  1. PaulBC says

    Tibetan monks get better at meditating, whatever that means;

    Adding “whatever that means” is unnecessarily dismissive. Tibetan Buddhist meditation means something very specific. A meditative state is externally measurable, and it is not something people attain without practice. I agree that it does not change the structure of the brain in some radical way, but I just think that your point could have been made better without letting the judgment creep into it.

    Personally, I think that practicing some form of meditation has value in terms of responding to stress, for example, and can help a lot of people. Granted, most people would not find value in meditating as much as a Tibetan monk.

  2. Sastra says

    Yes, they treat ‘neuroplasticity’ the same way they treat quantum mechanics. Pretend that there’s a dark, benighted group of materialists denying the science because they don’t like the spiritual conclusions it’s leading towards. Whereas the only ones distorting or denying the science are the ones trying to insert supernatural mind-body connections into well-established theories.

    I once had a group of woosters inform me that MRIs of the brain showed that when people meditate there are changes in the brain. They seemed to think that this conclusively supported mind-brain dualism. I told them no; if they were meditating and the MRI showed NO changes in the brain, then THAT would support mind-brain dualism.

    They couldn’t understand that point. They laughed because I wasn’t getting it. I was being obtuse.

  3. neuroturtle says

    Magical evil Stress Hormones, too. Because cortisol has only one function, and that is to destroy your brain. Buy my book about how it’s your fault you’re sick because you’re too negative!

  4. consciousness razor says

    PaulBC:

    Tibetan monks get better at meditating, whatever that means;

    Adding “whatever that means” is unnecessarily dismissive. Tibetan Buddhist meditation means something very specific.

    A bit oversensitive, aren’t we? What if he’s not being dismissive about that, but simply doesn’t know/care what (if anything) it very specifically means to you or anyone else? I would assume that if anything is being dismissed, it’s the attempt to validate “Eastern medicine” and other wooish crap that tends to come along for the ride, not meditation per se. Whatever it does really mean (if anything) makes no difference to whether or not learning has anything to do with it, so that can and should be set aside (in this thread, for the sake of focusing on the claims about neuroplasticity), in case anyone would want to dispute that. That’s one reading of it that makes sense to me, at least.

  5. mykroft says

    He’s focusing on how the brain can rewire to improve function or repair damage. One aspect of neuroplasticity that is often disregarded is the fact that the brain prunes down the number of neurons in the brain during the teen years. This is a critical time when the young brain is gaining efficiency by getting rid of neurons not being actively used. I interpret this as implying that young people are in a use it of lose it situation during this period.

    Another byproduct of this pruning is that external factors (like smoking marijuana) can negatively impact this process, which is why people shouldn’t try weed until age 22 or older.

  6. rama09 says

    Thanks for this article.

    They are currently looking at introducing ‘brain training’ in Australian schools, with the rationale that the ‘latest discoveries’ in Neuroplasticity suggest that with brain training, students can reach otherwise unreachable heights. Unfortunately, teachers and principals are presented with these concepts as if they are cutting edge and are left believing that it is true. I am trying to stop the spread of misinformation as I work in a school advisory organisation, but it is very difficult with limited articles attacking brain training and pseudo-neuroplasticity ideas, such as this one.

    It does seem as though the whole brain training industry seems to be full of charlatans and they love the word ‘neuroplasticity’.

  7. PaulBC says

    consciousness razor #5

    A bit oversensitive, aren’t we? What if he’s not being dismissive about that, but simply doesn’t know/care what (if anything) it very specifically means to you or anyone else? I would assume that if anything is being dismissed, it’s the attempt to validate “Eastern medicine” and other wooish crap that tends to come along for the ride, not meditation per se.

    I may be wrong, but I as far as I understand it, a meditative state can be detected in an EEG. So it’s really not about what it specifically means to me in a subjective sense. Tibetan monks get good at a particular mental discipline with practice. It’s as real and empirically based as the skill of knowing how to drive a taxi around Manhattan. I agree with your explanation of why PZ phrased it that way, but it just seems a little closed minded to me. You may not value being able to meditate like a Tibetan Buddhist. It’s not something I value enough to learn how. But it definitely means something, unlike, say, water divination or speaking in tongues. Some people are good at it, and a fraud could be detected experimentally.

  8. Broken Things says

    The November 2014 issue of Scientific American had an article that described observation of brain activity and the changes that occurred in the brain as a result of meditation. Their claims are much less extravagant than Doidge’s. They do document physical (volume) changes in the brain and claim that practitioners are less prone to some types of stress, but in conclusion the authors only say that studies “demonstrate that contemplative practices may have a substantive impact on biological processes critical for physical health.”

    Article is behind a pay wall but link here is to a video that is a talk by two of the authors.

  9. consciousness razor says

    But it definitely means something, unlike, say, water divination or speaking in tongues. Some people are good at it, and a fraud could be detected experimentally.

    What the hell is that supposed to mean? “Water divination” and “speaking in tongues” mean specific things, don’t they? You pretend to find water with your magic powers and you babble incoherently. That’s what they mean, respectively, and you could detect those sorts of frauds experimentally too.

  10. unclefrogy says

    mr razor it sounded like the reaction was to your implication that it, meditation, was BS. Which I assume is from the association meditation has with religious belief. The comment was about the neural activity of the brains doing the meditation as a learned mental activity regardless of the religious motivation for doing it.
    I think it fit in fine with the subject of neuroplasticity discussed here but not the main thing other than an example of the phenomena.
    uncle frogy

  11. says

    What I absolutely hate about neuroplasticity hype is that no one knows why a neuron that is doing its job would drop what it is doing and take on the functionality of a neighboring neuron. No one knows what signals are sent between neurons. Without this knowledge neuroplasticity is not truly scientifically repeatable. Nanowires could be used to listen to signals.

  12. robro says

    While neuroplasticity may be old hat to biologists, it’s a relatively new idea for us lay people. While I’m sure there’s general interest, I suspect recent interest has something do with parents of children with autism spectrum disorder…whatever that is…seeking a modicum of hope for their child. As one of those parents, I can testify that you will run into the concept as you try to understand what is happening to your child and what might be done about it. For course, all of this makes it ripe for exploitation by someone wanting to sell a book, a seminar seat, a lecture booking, or a treatment.

  13. opposablethumbs says

    robro, as you’ve probably seen there are a handful of us around here in roughly related, if not the same, boats; just on the off-chance that it is of any relevance in your child’s case, one good thing in our case (and which at the very least I’m pretty sure actually can’t do any harm! and should not be a rip-off) turned out to be music (making, rather than only listening to). Helped alleviate communication frustrations, among other things. Your family’s MMV, of course, I don’t mean to presume.

  14. moarscienceplz says

    Doidge claims much more, using poorly sourced anecdotes of people curing themselves of Parkinson’s or restoring their sight by thinking and carrying out various exercises.

    Professor Harold Hill is alive and well.

  15. PaulBC says

    consciousness razor #11

    What the hell is that supposed to mean? “Water divination” and “speaking in tongues” mean specific things, don’t they?

    They mean different things to different people (which is also true of meditation and taxi-driving, so I admit it’s a fine distinction).

    If I stated walking around with a stick and claimed to look for water, a traditional dowser might object that I am a fraud because I’m not applying the technique they learned. Neither of us will actually be better at using the stick to find water (though possibly one of us might have better intuition about where to dig a well). So the question of whether I’m a fraud depends on the definition used. If I’ve entered some kind of traditional arts competition as a dowser, and just wing it, then it’s reasonable to call me, but not the dowser, a fraud. If the dowser and I have offered to find a place to dig a well, and claim that the stick is going to help, then we’re both frauds.

    I would define meditation it as reaching a particular, detectable mental state. If I pretend to meditate like a Tibetan Buddhist monk, I’m a fraud and can be found out, e.g. using an EEG.

    I admit it is a fine distinction between this and saying I have applied the wrong technique to dowse for water. But if the end result is finding water, then neither technique is effective. If the end result of meditation is reaching a particular mental state (and not some outlandish claim like being able to levitate) then the Tibetan Buddhist monk will be effective and I will not be.

    In part, my point is whether the end result of the learned skill matches the claim. In the case of taxi-driving, it is pretty clear cut that knowing the routes to take is well-defined. In the case of dowsing, no degree of skill in handling the stick is going to help me find water.

    Meditation is somewhat problematic, because there are religious claims that exceed merely attaining a meditative state for its own purpose. Though I share PZ’s dislike of woo, there is such as thing as a meditative state, and I had taken the most commonly understood definition of meditation as a practice aimed at reaching that state.

    I still think the original posting would have been better written if he had omitted the phrase “whatever that means” though it’s not a huge thing, just a minor quibble.